CPA4 and Familial prostate cancer: Subsequently, genomic studies revealed that the CPA4 gene was preferentially expressed by the maternal allele (paternally imprinted) and located at the prostate cancer aggressiveness locus on the 7q32 chromosome and was preferentially expressed in adult benign prostatic hyperplasia, but the expression in normal adult human tissues including prostate, ovary, testis, and pancreas was quite low, suggesting thatCPA4 may be related to prostate cancer aggressiveness [12,19,20].